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Free Financial Math Calculators

65 free tools · Interest rates, loan payments, investment returns, and more.

65 free financial math calculators

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Compound Interest Calculator

Calculate compound interest with monthly contributions, solve for principal, rate, or time, and see a year-by-year growth breakdown.

Simple Interest Calculator | I=PRT

Calculate simple interest using I = P × R × T formula.

Loan Payment Calculator

Calculate monthly loan payments, total interest, and amortization.

Tip Calculator | Split Bill

Calculate tip amount, total bill, and split between multiple people.

Mortgage Calculator | Monthly Payment

Calculate monthly mortgage payments, total interest, and amortization schedule.

ROI Calculator | Return on Investment

Calculate return on investment percentage from cost and revenue.

Currency Converter | Live Exchange Rates

Convert between 35 world currencies with live daily exchange rates. Shows mid-market rates, rate table, and popular pairs.

Depreciation Calculator | SL, DDB & SYD

Calculate annual depreciation and full amortization schedules using straight-line, double declining balance, and sum-of-years-digits methods. Includes book value chart and method comparison.

Income Tax Calculator | US 2024

Estimate your income tax based on US federal tax brackets (2024). Calculate effective tax rate.

Break-Even Calculator

Calculate the break-even point in units and revenue from fixed costs, variable costs, and selling price. Includes contribution margin, CM ratio, safety margin, operating leverage, target profit planning, and a visual break-even chart.

Retirement Savings Calculator

Project how much you will have at retirement based on savings rate, return, and time horizon.

Inflation Calculator | Purchasing Power

Calculate the purchasing power of money over time using historical or custom inflation rates.

NPV Calculator | Net Present Value

Calculate the net present value (NPV) and profitability index of an investment.

Debt Payoff Calculator | Credit Card & Loan

Calculate how long to pay off any debt and total interest paid. Includes amortization schedule, extra payment comparison, and find-required-payment mode for credit cards and loans.

Savings Goal Calculator

Calculate how long to reach a savings goal or the monthly contribution needed.

Salary to Hourly Calculator

Convert annual salary to hourly, daily, weekly, and monthly rates.

Hourly to Salary Calculator | Advanced Pay Converter

Convert any hourly wage to annual salary, monthly, bi-weekly, weekly, and daily pay. Includes benefits valuation, contractor vs employee cost comparison, gross-to-net tax estimate, multi-currency support, and PDF/CSV export.

GST / VAT Calculator | Add, Remove & Multi-Item

Add or remove GST/VAT from any price. Multi-item invoices with individual rates. Country presets for Australia, UK, India, Canada, and EU. 6 currencies supported.

Bill Splitter | Tip & Split

Split a restaurant bill with custom tip percentage and divide equally among any number of people.

Annuity Calculator | PV, FV, Payment, Term & Perpetuity

Calculate present value, future value, required payment, or term for ordinary annuities and annuities-due. Includes perpetuity mode, step-by-step working, and a year-by-year growth or amortization schedule.

APR Calculator | True Cost of Any Loan

Calculate the Annual Percentage Rate (APR) and Effective Annual Rate (EAR) for any loan. Accounts for upfront fees, shows step-by-step Newton-Raphson solution, and compares two loan offers side by side.

Fuel Cost Calculator | Trip Cost & CO2

Calculate trip fuel cost from distance, fuel efficiency, and price per litre. Supports L/100km, km/L, MPG US/UK, six currencies, CO2 estimate, and step-by-step working.

Auto Loan Calculator | Monthly Car Payment

Calculate your monthly car loan payment with down payment, trade-in, sales tax, and fees. Includes a full amortization schedule, rate sensitivity table, down payment impact analysis, and side-by-side loan comparison.

Investment Calculator | Growth, Returns & Retirement

Project long-term investment growth with monthly contributions and lump-sum inputs. Compare conservative, moderate, and aggressive return scenarios, see inflation-adjusted value, and estimate retirement income using the 4% withdrawal rule.

Net Worth Calculator | Assets, Debts & Financial Health

Calculate your net worth by listing all assets and liabilities. See how you compare to Federal Reserve age benchmarks, check your debt-to-asset ratio, and find your financial independence number.

Budget Calculator | 50/30/20 Rule & Monthly Planning

Build a monthly budget and compare your actual spending to the 50/30/20 rule. Track needs, wants, and savings against recommended targets, check emergency fund readiness, and see your personal savings rate.

Rent vs Buy Calculator | True Cost Comparison

Compare the true total cost of renting vs buying over any time horizon. Includes opportunity cost of the down payment, equity buildup, home appreciation, rent inflation, and break-even year.

Paycheck Calculator | Net Pay & Tax Withholding

Calculate your exact take-home pay after federal income tax, FICA, state taxes, and pre-tax deductions like 401(k) and health insurance. Supports all 50 states and all filing statuses.

Home Affordability Calculator | Max Price & DTI

Find the maximum home price you can afford based on income, debts, and down payment using the 28/36 DTI rule and FHA 43% maximum. Includes PMI estimate and PITI breakdown.

Student Loan Calculator | Repayment Plans & PSLF

Compare all federal student loan repayment plans (Standard, Graduated, Extended, IBR, PAYE, SAVE) with full IDR calculations, PSLF tracker, and private refinancing comparison.

Mortgage Refinance Calculator | Break-Even & Savings

Calculate your monthly savings, break-even month, and cumulative net savings from refinancing. Supports rate-term and cash-out refinancing with closing cost analysis.

CD Calculator | APY, Compounding & Early Withdrawal

Calculate Certificate of Deposit returns with APY, compounding frequency, early withdrawal penalty, and inflation-adjusted real return. Includes a 5-rung CD ladder builder.

Capital Gains Tax Calculator | 2024 Federal & State

Calculate federal and state capital gains tax on investments using 2024 LTCG brackets, NIIT (IRC § 1411), and all 50 states. Includes tax-loss harvesting scenario and holding period analysis.

Car Lease vs Buy Calculator | True Cost Comparison

Compare the true cost of leasing vs buying a car. Calculates lease payment from money factor and residual, total cost over the term, and equity advantage of buying.

College Savings Calculator | 529 & Tuition Projection

Project 4-year college costs with tuition inflation, calculate 529 savings growth, and find the monthly contribution needed to cover 50%–100% of projected costs.

FIRE Calculator | Financial Independence Number

Calculate your FIRE number using the 4% safe withdrawal rate, find your months to financial independence, Coast FIRE number, and see how savings rate affects your timeline.

Dividend Calculator | DRIP Returns & Yield on Cost

Project dividend income with DRIP reinvestment, dividend growth rate, and price appreciation over time. Compare reinvesting vs. taking cash and see yield on cost by year.

Social Security Calculator | Claiming Age & Benefits

Estimate your Social Security benefit at 62, FRA, and 70 using the 2024 PIA formula with bend points. Find your break-even age, compare claiming strategies, and calculate spousal benefits.

RMD Calculator | Required Minimum Distribution 2024

Calculate your Required Minimum Distribution (RMD) using the IRS Uniform Lifetime Table (2022 update). Includes SECURE 2.0 rules, 10-year projection, and penalty for missed RMDs.

401(k) & Roth IRA Calculator

Compare traditional 401(k) and Roth IRA contributions side by side. Project tax-deferred vs. tax-free growth, estimate employer match impact, and find the breakeven tax rate to decide which account wins.

Bond Price Calculator | YTM, Duration & Convexity

Calculate bond price from yield to maturity, coupon rate, and maturity. Find YTM from price, compute Macaulay and modified duration, convexity, and accrued interest for clean vs dirty price.

Dollar-Cost Averaging Calculator | DCA Returns

Simulate dollar-cost averaging vs. lump-sum investing over any period. Compare average cost per share, total invested, portfolio value, and risk-adjusted returns across market scenarios.

Emergency Fund Calculator | Target & Savings Plan

Calculate your ideal emergency fund size based on monthly expenses, job stability, and household risk. Get a month-by-month savings plan and see how much interest you could earn in a HYSA.

Rental Property Calculator | Cap Rate & Cash Flow

Analyze rental property returns with cap rate, cash-on-cash return, gross rent multiplier, NOI, and projected 10-year equity. Compare financing scenarios and calculate the 50% and 1% rules.

Options Pricing Calculator | Black-Scholes & Greeks

Price European call and put options using the Black-Scholes model. Calculate all five Greeks (Delta, Gamma, Theta, Vega, Rho), implied volatility, intrinsic vs. time value, and breakeven price.

Credit Card Payoff Calculator | Debt-Free Date

Calculate exactly when you will pay off your credit card debt and how much interest you will pay. Compare minimum payments vs fixed amounts, model avalanche and snowball strategies, and see how extra payments save you money.

Amortization Calculator | Full Payment Schedule

Generate a complete month-by-month amortization schedule for any loan. See exactly how much principal and interest you pay each month, your remaining balance, and the total cost of the loan over its full term.

CAGR Calculator | Compound Annual Growth Rate

Calculate compound annual growth rate (CAGR) from a beginning value, ending value, and number of years. Reverse-solve for required end value or time horizon. Compare CAGR across multiple investments side by side.

Present Value Calculator | PV of Future Cash Flows

Calculate the present value of a future lump sum or annuity stream. Discount future money back to today using any rate. Compare PV of multiple cash flows and understand the time value of money with step-by-step working.

Portfolio Rebalancer | Target Allocation & Drift Analysis

Rebalance your investment portfolio to target allocations. Analyze drift, generate buy/sell trade recommendations, and model cash additions. Supports up to 15 assets with a visual allocation chart and tax-lot awareness.

DRIP Calculator | Dividend Reinvestment & Compound Growth

Project dividend reinvestment plan (DRIP) growth over time. Enter shares, price, and yield; model dividend growth and price appreciation; see year-by-year shares accumulated, income, and total portfolio value with yield-on-cost progression.

Freelance Rate Calculator | Hourly & Project Pricing

Calculate the minimum hourly rate you must charge as a freelancer to hit your income goals. Accounts for taxes, billable vs non-billable hours, overhead, benefits gap, and vacation. Output includes day, week, and project rates with a breakeven analysis.

Mortgage Points Calculator | Discount Points Break-Even Analysis

Determine whether buying mortgage discount points makes financial sense. Compare up to four scenarios (0, 0.5, 1, 2 points) with monthly payment reduction, total interest savings, and exact break-even month. Includes a sell-before-break-even analysis.

CD Ladder Calculator | Multi-Rung Certificate of Deposit Strategy

Build a certificate of deposit ladder with 2 to 6 rungs, each with its own APY and term. See a complete maturity schedule, rolling reinvestment projections, total interest earned per rung, and how the ladder compares against putting everything in one CD.

Meeting Cost Calculator | Real-Time Meeting Expense Tracker

Calculate the true monetary cost of any meeting with a live ticking timer. Add multiple attendees with individual annual salaries, see the cost climb in real time, get a per-minute breakdown, and estimate how much your weekly recurring meetings cost the organization per year.

Loan Comparison Calculator | Compare 3 Loans Side by Side

Compare up to three loans simultaneously. Enter principal, interest rate, and term for each loan to see monthly payments, total interest paid, total cost, and a year-by-year remaining balance. Automatically ranks loans by cheapest total cost and highlights the best option.

Debt-to-Income Calculator | DTI Ratio & Mortgage Qualification

Calculate your front-end and back-end debt-to-income (DTI) ratios for mortgage and loan qualification. Enter all monthly debts and gross income to see whether you meet Conventional, FHA, and VA lending guidelines. Includes a reverse calculator to find your maximum loan amount.

Savings Withdrawal Calculator | How Long Will My Money Last?

Find out exactly how long your savings will last at any withdrawal rate, investment return, and inflation rate. Model the 4% rule, add annual contributions during drawdown, compare three return scenarios side by side, and use the sustainable rate finder to calculate the maximum withdrawal that never depletes savings over 30 years.

Closing Cost Calculator | Buyer & Seller Real Estate Fees

Estimate all closing costs for a home purchase or sale. Buyer side covers loan origination, title insurance, appraisal, prepaid interest, escrow reserves, and transfer taxes. Seller side shows net proceeds after agent commissions, payoff, and all settlement charges.

Overtime Pay Calculator | Hourly, OT & Double-Time Gross Pay

Calculate gross pay including regular, overtime (1.5×), and double-time (2×) earnings for any pay period. Supports FLSA federal rules, California daily OT rules, and custom multipliers. Shows a complete pay breakdown by rate type with annual projection.

Crypto Profit Calculator | Cryptocurrency P&L, ROI & Tax Estimator

Calculate cryptocurrency profit, loss, and ROI for any coin or token. Enter buy and sell prices with quantity to see net gain/loss, percentage return, short-term vs long-term capital gains tax estimate, and break-even price. Supports dollar-cost averaging across multiple entries.

HSA Calculator | Tax Savings, Contribution Limits & Investment Growth

Maximize your Health Savings Account with detailed tax savings across federal, state, and FICA contributions. Covers 2024–2025 IRS limits, age-55 catch-up amounts, investment growth projection, and a side-by-side comparison of spending HSA funds now versus investing for retirement.

Salary Negotiation Calculator | Compare Total Compensation Packages

Compare two job offers side-by-side on total compensation — not just base salary. Quantifies the dollar value of 401k match, health insurance, PTO days, remote work savings, equity/RSU, signing bonus, and annual raise trajectory. Shows true yearly and lifetime earnings difference.

Economic Order Quantity Calculator | EOQ, Reorder Point & Safety Stock

Calculate the optimal Economic Order Quantity (EOQ) using the Wilson formula √(2DS/H), together with reorder point (ROP), safety stock, cycle stock, average inventory, annual ordering cost, annual holding cost, and total inventory cost.

IRR Calculator | Internal Rate of Return, MIRR & Payback Period

Calculate the Internal Rate of Return (IRR) and Modified IRR (MIRR) for a series of up to 20 cash flows using the Newton-Raphson iterative method. Also computes net present value at any discount rate, discounted payback period, and profitability index.

About Financial Math Calculators

Financial math tools help you understand the true cost and value of money over time. Interest rates, loan payments, investment returns, inflation, and tax calculations all depend on compound arithmetic that is easy to get wrong with shortcuts. These calculators use industry-standard formulas.

Who uses these tools: Home buyers comparing mortgage options, investors projecting portfolio growth, students planning for retirement, business owners analysing profitability, and anyone negotiating a loan or salary.

Tips for best results: APR (Annual Percentage Rate) and APY (Annual Percentage Yield) are different. APR is the stated rate; APY accounts for compounding frequency and is always higher than or equal to APR. Use the APR calculator to convert between them before comparing financial products.

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